mybatis-plus结合springboot使用
mybatis-plus入门使用-代码仓库：https://gitee.com/DerekAndroid/mybatisPlusDemo.git
mybatis-plus入门使用：
1.sql准备
DROP TABLE IF EXISTS user;
CREATE TABLE user
(
id BIGINT(20) NOT NULL AUTO_INCREMENT COMMENT '主键ID',
name VARCHAR(30) NULL DEFAULT NULL COMMENT '姓名',
age INT(11) NULL DEFAULT NULL COMMENT '年龄',
email VARCHAR(50) NULL DEFAULT NULL COMMENT '邮箱',
PRIMARY KEY (id)
);
DELETE FROM user;
INSERT INTO user (id, name, age, email) VALUES
(1, 'Jone', 18, '[email protected]'),
(2, 'Jack', 20, '[email protected]'),
(3, 'Tom', 28, '[email protected]'),
(4, 'Sandy', 21, '[email protected]'),
(5, 'Billie', 24, '[email protected]');usertwo.sql
DROP TABLE IF EXISTS usertwo;
#创建用户表
CREATE TABLE usertwo (
id BIGINT(20) PRIMARY KEY NOT NULL COMMENT '主键',
name VARCHAR(30) DEFAULT NULL COMMENT '姓名',
age INT(11) DEFAULT NULL COMMENT '年龄',
email VARCHAR(50) DEFAULT NULL COMMENT '邮箱',
manager_id BIGINT(20) DEFAULT NULL COMMENT '直属上级id',
create_time DATETIME DEFAULT NULL COMMENT '创建时间',
CONSTRAINT manager_fk FOREIGN KEY (manager_id)
REFERENCES usertwo (id)
) ENGINE=INNODB CHARSET=UTF8;
#初始化数据：
INSERT INTO usertwo (id, name, age, email, manager_id
, create_time)
VALUES (1087982257332887553, '大boss', 40, '[email protected]', NULL
, '2019-01-11 14:20:20'),
(1088248166370832385, '王天风', 25, '[email protected]', 1087982257332887553
, '2019-02-05 11:12:22'),
(1088250446457389058, '李艺伟', 28, '[email protected]', 1088248166370832385
, '2019-02-14 08:31:16'),
(1094590409767661570, '张雨琪', 31, '[email protected]', 1088248166370832385
, '2019-01-14 09:15:15'),
(1094592041087729666, '刘红雨', 32, '[email protected]', 1088248166370832385
, '2019-01-14 09:48:16');2.springboot依赖+配置
4.0.0
org.springframework.boot
spring-boot-starter-parent
2.2.6.RELEASE
com.example
demo
0.0.1-SNAPSHOT
mybatisPlusDemo
Demo project for Spring Boot
1.8
org.springframework.boot
spring-boot-starter
org.springframework.boot
spring-boot-starter-test
test
org.junit.vintage
junit-vintage-engine
org.projectlombok
lombok
true
1.18.8
com.baomidou
mybatis-plus-boot-starter
3.3.1.tmp
mysql
mysql-connector-java
com.baomidou
mybatis-plus-boot-starter
3.3.1.tmp
com.baomidou
mybatis-plus-generator
3.3.1.tmp
org.freemarker
freemarker
2.3.30
junit
junit
4.12
compile
org.springframework.boot
spring-boot-starter-web
compile
org.springframework.boot
spring-boot-maven-plugin
逆向工程自动生成
根据创建好的数据库执行自动生成mybtais配置文件
注意：freemarker依赖需要配合模板使用
autoGenerator.setTemplateEngine(new FreemarkerTemplateEngine());自动生成类
package com.example.demo.test;
import com.baomidou.mybatisplus.annotation.DbType;
import com.baomidou.mybatisplus.annotation.IdType;
import com.baomidou.mybatisplus.generator.AutoGenerator;
import com.baomidou.mybatisplus.generator.config.DataSourceConfig;
import com.baomidou.mybatisplus.generator.config.GlobalConfig;
import com.baomidou.mybatisplus.generator.config.PackageConfig;
import com.baomidou.mybatisplus.generator.config.StrategyConfig;
import com.baomidou.mybatisplus.generator.config.rules.NamingStrategy;
import org.junit.Test;
public class SqlGenerator {
@Test
public void testGenerator(){
//0.获取当前主项目路径
String dir = System.getProperty("user.dir");
String outputDir=dir+"/src/main/java";
System.out.println("outputDir="+outputDir);
//1、全局配置
GlobalConfig config = new GlobalConfig();
config.setActiveRecord(true)//开启AR模式
.setAuthor("agen")//设置作者
//生成路径(一般都是生成在此项目的src/main/java下面)
.setOutputDir(outputDir)
.setFileOverride(true)//第二次生成会把第一次生成的覆盖掉
.setIdType(IdType.AUTO)//主键策略
.setServiceName("%sService")//生成的service接口名字首字母是否为I，这样设置就没有I
.setBaseResultMap(true)//生成resultMap
.setBaseColumnList(true);//在xml中生成基础列
//2、数据源配置
DataSourceConfig dataSourceConfig = new DataSourceConfig();
dataSourceConfig.setDbType(DbType.MYSQL)//数据库类型
.setDriverName("com.mysql.jdbc.Driver")
.setUrl("jdbc:mysql://localhost:3306/boot_user?useUnicode=true&characterEncoding=UTF-8&zeroDateTimeBehavior=convertToNull&serverTimezone=UTC")
.setUsername("root")
.setPassword("123");
//3、策略配置
StrategyConfig strategyConfig = new StrategyConfig();
strategyConfig.setCapitalMode(true)//开启全局大写命名
.setNaming(NamingStrategy.underline_to_camel)//下划线到驼峰的命名方式
.setTablePrefix("tb_")//表名前缀
.setEntityLombokModel(true)//使用lombok
.setInclude("user");//逆向工程使用的表
//4、包名策略配置
PackageConfig packageConfig = new PackageConfig();
packageConfig.setParent("com.example.demo")//设置包名的parent
.setMapper("mapper")
.setService("service")
.setController("controller")
.setEntity("entity")
.setXml("mapper");//设置xml文件的目录
//5、整合配置
AutoGenerator autoGenerator = new AutoGenerator();
autoGenerator.setGlobalConfig(config)
.setDataSource(dataSourceConfig)
.setStrategy(strategyConfig)
.setPackageInfo(packageConfig);
//6、执行
autoGenerator.execute();
}
}
生成的效果文件
按模板自动生成代码：
注意：baseEntity需要自己创建实现
package com.example.demo.test;
import com.baomidou.mybatisplus.annotation.DbType;
import com.baomidou.mybatisplus.annotation.IdType;
import com.baomidou.mybatisplus.generator.AutoGenerator;
import com.baomidou.mybatisplus.generator.config.DataSourceConfig;
import com.baomidou.mybatisplus.generator.config.GlobalConfig;
import com.baomidou.mybatisplus.generator.config.PackageConfig;
import com.baomidou.mybatisplus.generator.config.StrategyConfig;
import com.baomidou.mybatisplus.generator.config.rules.NamingStrategy;
import com.baomidou.mybatisplus.generator.engine.FreemarkerTemplateEngine;
import org.junit.Test;
public class SqlGenerator {
@Test
public void testOne(){
String dir = System.getProperty("user.dir");
String outputDir=dir+"/src/main/java";
System.out.println("outputDir="+outputDir);
//D:\java\code\mybatisPlusDemo/src/main/java
}
@Test
public void testGenerator(){
//0.获取当前主项目路径
String dir = System.getProperty("user.dir");
String outputDir=dir+"/src/main/java";
System.out.println("outputDir="+outputDir);
//1、全局配置
GlobalConfig config = new GlobalConfig();
config.setActiveRecord(true)//开启AR模式
.setAuthor("agen")//设置作者
//生成路径(一般都是生成在此项目的src/main/java下面)
.setOutputDir(outputDir)
.setFileOverride(true)//第二次生成会把第一次生成的覆盖掉
.setIdType(IdType.AUTO)//主键策略
.setServiceName("%sService")//生成的service接口名字首字母是否为I，这样设置就没有I
.setBaseResultMap(true)//生成resultMap
.setBaseColumnList(true);//在xml中生成基础列
//2、数据源配置
DataSourceConfig dataSourceConfig = new DataSourceConfig();
dataSourceConfig.setDbType(DbType.MYSQL)//数据库类型
.setDriverName("com.mysql.jdbc.Driver")
.setUrl("jdbc:mysql://localhost:3306/boot_user?useUnicode=true&characterEncoding=UTF-8&zeroDateTimeBehavior=convertToNull&serverTimezone=UTC")
.setUsername("root")
.setPassword("123");
//3、策略配置
StrategyConfig strategyConfig = new StrategyConfig();
strategyConfig.setCapitalMode(true)//开启全局大写命名
.setNaming(NamingStrategy.underline_to_camel)//下划线到驼峰的命名方式
.setTablePrefix("tb_")//表名前缀
.setEntityLombokModel(true)//使用lombok
.setInclude("children");//逆向工程使用的表
//4、包名策略配置
PackageConfig packageConfig = new PackageConfig();
packageConfig.setParent("com.example.demo")//设置包名的parent
.setMapper("mapper")
.setService("service")
.setController("controller")
.setEntity("entity")
.setXml("mapper");//设置xml文件的目录
//5、整合配置
AutoGenerator autoGenerator = new AutoGenerator();
autoGenerator.setGlobalConfig(config)
.setDataSource(dataSourceConfig)
.setStrategy(strategyConfig)
.setPackageInfo(packageConfig);
// 选择 freemarker 引擎需要指定如下加，注意 pom 依赖必须有！
autoGenerator.setTemplateEngine(new FreemarkerTemplateEngine());
//6、执行
autoGenerator.execute();
}
}
控制台输入模块us ,输入表名usertwo
生成的文件目录
4编写查询语句
package com.example.demo.service.impl;
import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.example.demo.entity.User;
import com.example.demo.mapper.UserMapper;
import com.example.demo.service.UserService;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
/**
*
* 服务实现类
*
*
* @author agen
* @since 2020-04-17
*/
@Service
@Slf4j
public class UserServiceImpl extends ServiceImpl implements UserService {
@Autowired
private UserMapper userMapper;
public void insertUser(User user) {
log.info("----------------插入一条记录： insert user----------------");
userMapper.insert(user);
}
public void serviceSave(User user) {
log.info("----------------service插入一条记录： save user----------------");
save(user);
}
public void selectTest() {
log.info("----------------按主键查询： where id=2----------------");
User user = userMapper.selectById(1);
log.info(user.toString());
log.info("----------------按主键查询： where id=2 ? and age=?----------------");
User user1 = new User();
user1.setId(2L);
user1.setAge(20);
QueryWrapper queryWrapper = new QueryWrapper<>(user1);
User user2 = userMapper.selectOne(queryWrapper);
log.info(user2.toString());
}
}
分页插件
1.配置文件
//Spring boot方式
@Configuration
@MapperScan("com.example.demo.mapper")
public class MybatisPlusConfig {
@Bean
public PaginationInterceptor paginationInterceptor() {
PaginationInterceptor paginationInterceptor = new PaginationInterceptor();
// 设置请求的页面大于最大页后操作， true调回到首页，false 继续请求 默认false
// paginationInterceptor.setOverflow(false);
// 设置最大单页限制数量，默认 500 条，-1 不受限制
// paginationInterceptor.setLimit(500);
// 开启 count 的 join 优化,只针对部分 left join
paginationInterceptor.setCountSqlParser(new JsqlParserCountOptimize(true));
return paginationInterceptor;
}
}2.测试自带分页
package com.example.demo;
import com.baomidou.mybatisplus.core.toolkit.Wrappers;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.example.demo.entity.User;
import com.example.demo.mapper.UserMapper;
import lombok.extern.slf4j.Slf4j;
import org.junit.jupiter.api.Test;
import org.junit.runner.RunWith;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;
import javax.annotation.Resource;
@Slf4j
@RunWith(SpringRunner.class)
@SpringBootTest
class DemoApplicationTests {
@Resource
private UserMapper mapper;
@Test
void contextLoads() {
System.out.println(("----- selectAll method test ------"));
}
@Test
public void testSlf4j() {
log.error("----------------------------------baseMapper 自带分页-------------------------------------------------------");
Page page = new Page<>(1, 3);
Page userIPage = mapper.selectPage(page, Wrappers.lambdaQuery().ge(User::getAge, 1).orderByDesc(User::getId));
log.error("总数据 -------------> {}", userIPage.getRecords().toArray());
log.error("总条数 -------------> {}", userIPage.getTotal() + "当前页数 -------------> {}" + userIPage.getCurrent() +
"当前每页显示数 -------------> {}" + userIPage.getSize());
}
}
json 正反序列化
@Test
public void testSlf4j() {
log.error("----------------------------------baseMapper 自带分页-------------------------------------------------------");
Page page = new Page<>(1, 3);
page.addOrder(OrderItem.asc("age"));
Page userIPage = mapper.selectPage(page, Wrappers.lambdaQuery().ge(User::getAge, 20));
log.error("总数据 -------------> {}", userIPage.getRecords().toString());
log.error("总条数 -------------> {}", userIPage.getTotal() + "当前页数 -------------> {}" + userIPage.getCurrent() +
"当前每页显示数 -------------> {}" + userIPage.getSize());
log.error("----------------------------------json 正反序列化-------------------------------------------------------");
log.info("page ----------> {}", page.getRecords().toString());
String json = JSON.toJSONString(page);
log.info("json ----------> {}", json);
//{"current":1,"hitCount":false,"orders":[],"pages":6,"records":[{"age":24,"email":"[email protected]","id":17,"name":"Billie"},{"age":21,"email":"[email protected]","id":16,"name":"Sandy"},{"age":28,"email":"[email protected]","id":15,"name":"Tom"}],"searchCount":true,"size":3,"total":17}
}
//反序列化 json->object
Page page1 = JSON.parseObject(json, new TypeReference>() {
});
log.info("page1.getRecords ----------> {}", page1.getRecords());
//[User(id=2, name=Jack, age=20, [email protected]), User(id=14, name=Jack, age=20, [email protected]), User(id=13, name=Jack, age=20, [email protected])]
} 表名、表字段改变，同步绑定操作
通过配置TableName同步更新表明
@TableName("user")
public class User extends Model {
private static final long serialVersionUID=1L;
/**
* 主键ID
*/
@TableId(value = "id", type = IdType.AUTO)
private Long id;
/**
* 姓名
*/
@TableField("name")
private String name; 配置多个mapper路径
springboot项目有时会涉及多数据源，因为我们通常每个数据源创建不同的包路径，mapper.xml的路径也不一样，这个时候就需要引入多个路径。
数据源1，mapper接口路径在 mapper包下面，mapper.xml 路径在 resources/mappers/下面；
数据源2，mapper接口路径在 mapper/other包下面，mapper.xml 路径在 resources/mappers/other下面：
配置总共分两步：
第一步 ：
在mybatisplus配置类里面修改扫描包路径：
@SpringBootApplication
@MapperScan({"com.example.demo.mapper","com.example.demo.**.mapper"})
public class DemoApplication {
public static void main(String[] args) {
SpringApplication.run(DemoApplication.class, args);
}
}第二步：
修项目的application.yml配置文件中配置mapper.xml路径如下：
mybatis-plus:
# 1.配置多个classpath：用,分割开 2.Maven 多模块项目的扫描路径需以 classpath*: 开头 （即加载多个 jar 包下的 XML 文件）
mapper-locations: classpath*:/mapper/us/*Mapper.xml,classpath*:/mapper/*Mapper.xml使用 Wrapper 自定义SQL
注意，如果使用xml方式，需要配置正确的路径
此处采用注解+xml的形式
public interface UserMapper extends BaseMapper {
@Select("SELECT * FROM user where name = #{name}")
List selectByName(@Param("name") String name);
List selectByNameTwo(@Param("name") String name);
@Select("select * from user ${ew.customSqlSegment}")
List mySelectMap(@Param(Constants.WRAPPER) Wrapper wrapper);
} xml配置
测试
@Test
public void testMap() {
log.info("------------------------------使用 Wrapper 自定义SQL---------->-");
QueryWrapper wrapper = new QueryWrapper();
wrapper.like("name", "m").eq("age", 28);
List name = mapper.mySelectMap(wrapper);
log.info("name----------> {}" + name.toString());
List users = mapper.selectByName("Tom");
log.info("name----------> {}" + users.toString());
log.info("------------------------------使用 Wrapper.xml文件 自定义SQL---------->-");
List tom = mapper.selectByNameTwo("Tom");
log.info("tom----------> {}" + tom.toString());
} 条件查询
@Test
public void testUserTwo() {
log.info("------------------------------查询全部--------->-");
List usertwos = usertwoMapper.selectList(null);
log.info("usertwos----------> {}" + usertwos.toString());
log.info("------------------------------SELECT * FROM usertwo WHERE name like '%雨%' and age<40--------->-");
QueryWrapper wrapper = new QueryWrapper();
wrapper.like("name", "雨").lt("age", 40);
List usertwos0 = usertwoMapper.selectList(wrapper);
log.info("usertwos0----------> {}" + usertwos0.toString());
// 名字中包含雨年并且龄大于等于20且小于等于40并且email不为空
log.info("------------------------------SELECT * FROM usertwo WHERE name like '%雨%' and age between 20 and 40 and email is not null--------->-");
QueryWrapper wrapper1 = new QueryWrapper();
wrapper.like("name", "雨").between("age", 20, 40).isNotNull("email");
List usertwos1 = usertwoMapper.selectList(wrapper);
log.info("usertwos1-----123-----> {}" + usertwos1.toString());
//名字为王姓或者年龄大于等于25，按照年龄降序排列，年龄相同按照id升序排列
log.info("------------------------------name like '王%' or age>=25 order by age desc,id asc--------->-");
QueryWrapper wrappe2 = new QueryWrapper();
wrappe2.likeRight("name", "王").or().ge("age", "25").orderByDesc("age").orderByAsc("id");
List usertwos2 = usertwoMapper.selectList(wrappe2);
log.info("usertwos2----------> {}" + usertwos2.toString());
//创建日期为2019年2月14日并且直属上级为名字为王姓
log.info("------------------------------date_format(create_time,'%Y-%m-%d')='2019-02-14' and manager_id in (select id from user where name like '王%')--------->-");
QueryWrapper wrappe3 = new QueryWrapper();
wrappe3.apply("date_format(create_time,'%Y-%m-%d') = {0}", "2019-02-14").inSql("manager_id", "select id from usertwo where name like '王%'");
List usertwos3 = usertwoMapper.selectList(wrappe3);
log.info("usertwos3----------> {}" + usertwos3.toString());
// 5、名字为王姓并且（年龄小于40或邮箱不为空）
log.info("------------------------------name like '王%' and (age<40 or email is not null)--------->-");
QueryWrapper wrapper4 = new QueryWrapper<>();
wrapper4.likeRight("name", "王").and(i -> i.lt("age", 40).or().isNotNull("email"));
List usertwos4 = usertwoMapper.selectList(wrapper4);
log.info("usertwos4----------> {}" + usertwos4.toString());
// 6、名字为王姓或者（年龄小于40并且年龄大于20并且邮箱不为空）
log.info("------------------------------name like '王%' or (age<40 and age>20 and email is not null)--------->-");
QueryWrapper wrapper5 = new QueryWrapper<>();
wrapper5.likeRight("name", "%王%").or(wq -> wq.lt("age", 40).gt("age", 20).isNotNull("email"));
List usertwos5 = usertwoMapper.selectList(wrapper5);
log.info("usertwos5----------> {}" + usertwos5.toString());
// 7、（年龄小于40或邮箱不为空）并且名字为王姓
log.info("------------------------------(age<40 or email is not null) and name like '王%'--------->-");
QueryWrapper wrapper6 = new QueryWrapper<>();
wrapper6.nested(wq -> wq.lt("age", 40).isNotNull("email")).likeRight("name", "%王%");
wrapper6.likeRight("name", "%王%").and(wq -> wq.lt("age", 40).isNotNull("email"));
List usertwos6 = usertwoMapper.selectList(wrapper6);
log.info("usertwos6----------> {}" + usertwos6.toString());
// 8、年龄为30、31、34、35
log.info("------------------------------age in(30,31,34,35)--------->-");
QueryWrapper wrapper7 = new QueryWrapper<>();
wrapper7.in("age", 30, 31, 32, 34, 35);
List usertwos7 = usertwoMapper.selectList(wrapper7);
log.info("usertwos7----------> {}" + usertwos7.toString());
//拉姆达表达式的语法糖 list.forEach((String t) -> System.out.println(t));
usertwos7.forEach(System.out::println);
// 9、只返回满足条件的其中一条语句即可
log.info("------------------------------age in(30,31,34,35)--------->-");
QueryWrapper wrapper8 = new QueryWrapper<>();
wrapper8.in("age", 30, 31, 32, 34, 35).last("limit 1");
List usertwos8 = usertwoMapper.selectList(wrapper8);
log.info("usertwos8----------> {}" + usertwos8.toString());
}
select中字段不全部出现的查询
@Test
public void testSelect() {
log.info("select中字段不全部出现的查询");
// 10、名字中包含雨并且年龄小于40(需求1加强版)
log.info("---------------------select id,name from usertwo where name like '%雨%' and age<40------------------>-");
QueryWrapper wrapper1 = new QueryWrapper<>();
wrapper1.select("id", "name").like("name", "雨").lt("age", 40);
List usertwos1 = usertwoMapper.selectList(wrapper1);
log.info("usertwos1----------> {}" + usertwos1.toString());
log.info("----------------------select id,name,age,email from usertwo where name like '%雨%' and age<40----------------------->");
QueryWrapper wrapper2 = new QueryWrapper<>();
wrapper2.select(Usertwo.class, qw -> !qw.getColumn().equals("manager_id") && !qw.getColumn().equals("create_time")).like("name", "雨").lt("age", 40);
List usertwos2 = usertwoMapper.selectList(wrapper2);
log.info("usertwos2----------> {}" + usertwos2.toString());
} condition判断条件
@Test
public void testCondition() {
log.info("------------------------------condition判断条件--------->-");
QueryWrapper wrapper1 = new QueryWrapper<>();
String name = "雨";
String email = "";
//第一个入参boolean condition表示该条件是否加入最后生成的sql中.email为空，所以不查询
//SELECT name,age FROM usertwo WHERE (name LIKE ?)
wrapper1.like(!StringUtils.isEmpty(name), "name", name).like(!StringUtils.isEmpty(email), "email", email).select("name", "age");
List usertwos1 = usertwoMapper.selectList(wrapper1);
log.info("usertwos1----------> {}" + usertwos1.toString());
} insert数据的时候，如何排除非表中字段
@Test
public void testExit() {
log.info("------------------------------insert数据的时候，如何排除非表中字段？--------->-");
User user = new User();
user.setName("agen");
user.setAge(18);
user.setMessgeFlag("我是用来标记的信息,不会存放在数据库中");
int insert = mapper.insert(user);
log.info("insert----------> {}" + insert);
}主键策略-id
sql
DROP TABLE IF EXISTS userthree;
CREATE TABLE userthree
(
id BIGINT(20) NOT NULL AUTO_INCREMENT COMMENT '主键ID',
name VARCHAR(30) NULL DEFAULT NULL COMMENT '姓名',
age INT(11) NULL DEFAULT NULL COMMENT '年龄',
email VARCHAR(50) NULL DEFAULT NULL COMMENT '邮箱',
PRIMARY KEY (id)
);
DELETE FROM userthree;
INSERT INTO userthree (id, name, age, email) VALUES
(1, 'Jone', 18, '[email protected]'),
(2, 'Jack', 20, '[email protected]'),
(3, 'Tom', 28, '[email protected]'),
(4, 'Sandy', 21, '[email protected]'),
(5, 'Billie', 24, '[email protected]');测试代码
@Test
public void testInsertUserThree() {
log.info("------------------------------ UserThree insert数据--------->-");
Userthree usertwo = new Userthree();
usertwo.setName("agen");
usertwo.setAge(18);
usertwo.setEmail("[email protected]");
int insert = userthreeMapper.insert(usertwo);
log.info("insert----------> {}" + insert);
}#auto自动增加，5->6
@TableId(value = "id", type = IdType.AUTO)
private Long id;Preparing: INSERT INTO userthree ( name, age, email ) VALUES ( ?, ?, ? )
#默认使用(IdWorker)推特雪花算法生成id
修改主键类型
ALTER TABLE userthree CHANGE COLUMN id id BIGINT(20);代码
@TableId(value = "id", type = IdType.NONE)
@TableId(value = "id", type = IdType.ID_WORKER)
private Long id;Preparing: INSERT INTO userthree ( id, name, age, email ) VALUES ( ?, ?, ?, ? )
Parameters: 1254971356540428289(Long), agen(String), 18(Integer), [email protected](String)
#字符类型uuid
修改主键类型
ALTER TABLE userthree CHANGE COLUMN id id VARCHAR(32) NOT NULL;代码
@TableId(value = "id", type = IdType.UUID)
private String id;
Preparing:INSERT INTO userthree ( id, name, age, email ) VALUES ( ?, ?, ?, ? )
Parameters: c49fc6bb50330e33de7f57ec718e7ee8(String), agen(String), 18(Integer), [email protected](String)
#字符类型-IdWorker雪花算法
@TableId(value = "id", type = IdType.ID_WORKER_STR)
Preparing: INSERT INTO userthree ( id, name, age, email ) VALUES ( ?, ?, ?, ? )
Parameters: 1254979400980598786(String), agen(String), 18(Integer), [email protected](String)
整体效果：
